OF THE LATE JOHN KENNEDY^ ESQ. 151 



account in his " Memoir of Crompton :'^ — " It was not 

 until 1793 ^^^^ ^^y attempts were made in spinning fine 

 yarnSj say from one hundred hanks upwards, by power, 

 when I observed the process very carefully. The rollers^ 

 according to the fineness of the thread, would only admit 

 of a certain velocity per minute ; for instance, with two 

 hundreds, the rollers could only go ninety at the rate of 

 twenty-five or twenty-six revolutions per minute, and the 

 spindle about twelve hundred. But when the rollers 

 ceased to move, then the spindle was accelerated by the 

 spinner to nearly double its former speed. In what 

 manner the acceleration of the speed of the spindle might 

 be effected by machinery, without the aid of the spinner, 

 had occurred to me, by observing in Mr. Watt's steam 

 engine that one revolution of the beam (if I may use 

 the expression) acting upon the fly-wheel by means of 

 the sun and planet wheels, produced a double velocity. 

 The difficulty, however, of making the necessary appa- 

 ratus at that time induced me to use the more com- 

 plicated method of four wheels of unequal sizes for pro- 

 ducing the same efiect. The description is as follows : — 

 Two of the wheels were less and two larger ; upon the rim 

 axis one of the small and one of the large ; and the two 

 others were fixed in a frame which carried the axis upon 

 which they were placed, and which had a shank or axis 

 growing to it. This was placed in a vertical position, so 

 that when the carriage was put up an arm projecting from 

 this vertical shank was connected by a wire with a catch, 

 which kept the lying shaft that turned the rollers in gear. 

 In the elongating process the smaller wheel was in contact 

 with the larger wheel upon the rim, but when by the 

 disengagement of the catch the rollers became still or 

 stationary, at that moment the larger wheel, by means of 

 a weight, came in contact with the lesser wheel upon the 

 rim or axis, to which it communicated a double velocity. 



